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authornobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2018-07-06 08:01:58 (GMT)
committernobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2018-07-06 08:01:58 (GMT)
commit5e7167f8fb954ec46eb12a4a0a1191a8f7d9543d (patch)
treeee282abc39fd8e887ebc4ee19aaa85ecfc57c000 /compile.c
parent79f01d3972811e4388a257decea3e47445b42b59 (diff)
compile.c: remove unreachable jump only
* compile.c (iseq_peephole_optimize): remove unreachable jump instruction only. if it is labeled and referred from other instructions, it is reachable and must not be removed. [ruby-core:87830] [Bug #14897] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63870 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'compile.c')
-rw-r--r--compile.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/compile.c b/compile.c
index 139a778..6cd25ef 100644
--- a/compile.c
+++ b/compile.c
@@ -2730,12 +2730,13 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
ELEM_INSERT_NEXT(&dniobj->link, &pop->link);
goto again;
}
- else if (IS_INSN(iobj->link.prev) &&
- (piobj = (INSN *)iobj->link.prev) &&
+ else if ((piobj = (INSN *)get_prev_insn(iobj)) != 0 &&
(IS_INSN_ID(piobj, branchif) ||
IS_INSN_ID(piobj, branchunless))) {
INSN *pdiobj = (INSN *)get_destination_insn(piobj);
if (niobj == pdiobj) {
+ int refcnt = IS_LABEL(piobj->link.next) ?
+ ((LABEL *)piobj->link.next)->refcnt : 0;
/*
* useless jump elimination (if/unless destination):
* if L1
@@ -2753,7 +2754,12 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
piobj->insn_id = (IS_INSN_ID(piobj, branchif))
? BIN(branchunless) : BIN(branchif);
replace_destination(piobj, iobj);
- ELEM_REMOVE(&iobj->link);
+ if (refcnt <= 1) {
+ ELEM_REMOVE(&iobj->link);
+ }
+ else {
+ /* TODO: replace other branch destinations too */
+ }
return COMPILE_OK;
}
else if (diobj == pdiobj) {